CALOR Butane Regulator 21mm Butane Quick on 29mbar. CALOR GAS approved with 5 year warranty. Low pressure Butane gas regulator for use with portable heaters range with 21mm Clip-on inlet connection, and effortless on/off lever to clearly indicate when your gas is switched on or off. Fits: CALOR GAS 15kg, 13kg, 12kg & 7kg Butane Cylinders.